Reliability and relationship of colposcopical, cytological and histopathological findings in the diagnostic process

The question about the accuracy of cytology and colposcopy is more and more asked due to false positive and negative findings on the basis of which the decision on biopsy is made. The aim of this study was to examine reliability of biopsies based only on abnormal colposcopical findings, before receiving the results of Papanicolaou (PA) smear, by comparing findings of colposcopical, cytological and histopathological (HP) examinations as well as determining validity of these diagnostic methods.

The study involved all patients who had their regular colposcopical and cytological examinations in the outpatient department during a two-year period (2009-2010) in the Clinic for Gynecology and Obstetrics, Clinical Center of Serbia, Belgrade. The material for HP examination was obtained by colposcopically directed biopsy, due to abnormal colposcopical findings and without waiting for PA smear results. The data obtained by these methods were statistically analyzed and compared. Furthermore, validity of colposcopical and cytological examinations was assessed. Results. Out of 127 patients highly significantly more patients had more malignant cervical changes on colposcopical exam compared to HP (p = 0.000), and cytological exam (p = 0.000). Highly significantly more patients had more malignant cervical changes on PA smear than HP exam (p = 0.000), unless when findings were assessed in the widest sense of benign and malignant changes when there were no significant differences in these findings (p = 0.450). Sensitivity of colposcopy as a diagnostic method was 87.5%, specificity 24.14%, positive predictive value (+PV) was 34.65% and negative predictive value (-PV) 80.77%. Sensitivity of PA smear as a diagnostic method was 62.5%, specificity 87.36%, +PV was 69.44%, and -PV 83.52%.

Regarding the results of our study it is best to make a decision on treatment according to findings of all the three methods. Cytological analysis is more reliable than colposcopical examination. Therefore, it is advisable that following abnormal colposcopical findings, PA smear should always be taken and only after receiving the results further diagnostics can be planned (biopsy and HP). A final decision on the therapy has to be made based on HP findings which are the only method that can give the ultimate reliable diagnosis of cervical changes.